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Purpose Smart cities provide fully integrated and networked connectivity between virtual/digital assets and physical building/infrastructure assets to form digital economies. However, industrial espionage, cyber-crime and deplorable politically driven cyber-interventions threaten to disrupt and/or physically damage the critical infrastructure that supports national wealth generation and preserves the health, safety and welfare of the populous. The purpose of this paper is to present a comprehensive review of cyber-threats confronting critical infrastructure asset management reliant upon a common data environment to augment building information modelling (BIM) implementation. Design/methodology/approach An interpretivist, methodological approach to reviewing pertinent literature (that contained elements of positivism) was adopted. The ensuing mixed methods analysis: reports upon case studies of cyber-physical attacks; reveals distinct categories of hackers; identifies and reports upon the various motivations for the perpetrators/actors; and explains the varied reconnaissance techniques adopted. Findings The paper concludes with direction for future research work and a recommendation to utilize innovative block chain technology as a potential risk mitigation measure for digital built environment vulnerabilities. Originality/value While cyber security and digitization of the built environment have been widely covered within the extant literature in isolation, scant research has hitherto conducted an holistic review of the perceived threats, deterrence applications and future developments in a digitized Architecture, Engineering, Construction and Operations (AECO) sector. This review presents concise and lucid reference guidance that will intellectually challenge, and better inform, both practitioners and researchers in the AECO field of enquiry.

Purpose: Tracked hydraulic excavators are versatile and ubiquitous items of off-highway plant and machinery that are utilised throughout the construction industry. Each year a significant number of excavators overturn whilst conducting a lifting operation, causing damage to property, personnel injury or even fatality. The reasons for the overturn are myriad, including: operational or environmental conditions; machine operator acts or omissions; and/ or inadequate site supervision. Furthermore, the safe working load (SWL) figure obtained from manufacturer guidance and utilised in lift plans is based upon undertaking a static load only. This research seeks to determine whether the SWL is still safe to be used in a lift plan when slewing a freely suspended (dynamic) load, and if not, whether this may be a further contributory factor to overturn incidents. Approach: Previous research has developed a number of machine stability test regimes but these were largely subjective, impractical to replicate and failed to accurately measure the 'dynamic' horizontal centrifugal force resulting from slewing the load. This research contributes towards resolving the stability problem by critically evaluating existing governing standards and legislation, investigating case studies of excavator overturn and simulating the dynamic effects of an excavator when slewing a freely suspended load at high rotations per minute (rpm). To achieve this, both the static load and horizontal centrifugal force from slewing this load were calculated for six randomly selected cases of an excavator, with different arm geometry configurations. Findings: The results from the six cases are presented and a worked example of one is detailed to demonstrate how the results were derived. The findings reveal that the SWL quoted on an excavator's lift rating chart considerably underestimates the extra forces experienced by the machine when an additional dynamic load is added to the static load whilst lifting and slewing a freely suspended load. Originality: This work presents the first attempt to accurately model excavator stability by taking consideration of the dynamic forces caused by slewing a freely suspended load and will lead to changes in the way that industry develops and manages lift plans. Future research proposes to: vary the weight of load, arm geometry and rpm to predict machine stability characteristics under various operational conditions; and exploit this modelling data to populate pre-programmed sensor based technology to monitor stability in real time and automatically restrict lift mode operations.

Technology transfer (TT) is crucial to social infrastructure and economic development in developing countries (DCs). In Ghana's construction sector, foreign firms provide an invaluable source of innovation and technological advancement for local contractors. However, TT models published in existing literature are rarely applicable to the construction industry in DCs. This paper therefore presents a conceptual framework of the TT process as a tool for measuring construction performance. Utilising the results from a questionnaire survey of Ghanaian construction industry professionals, eight different perspectives on TT were formulated using exploratory factor analysis. These perspectives represent the enablers and outcomes of the TT process, namely transferor and transferee characteristics, knowledge advancement, the transfer environment, government influence, the learning environment, project performance, communication, and relationship building and absorptive capability. The research outcomes provide useful guidance to local and international funding agencies, governments of developing or newly industrialised countries, and construction firms that seek to effectively evaluate the success (or otherwise) of the TT process. Future research should seek to validate the research findings presented, and to expand the work to include other DCs.

Purpose The purpose of this study is to explore the mortgage affordability problem in Ghana, an issue that has been associated inter alia with high mortgage rates, which results from the high cost of capital, an unstable macroeconomy and unfavourable borrowers' characteristics. Concurrent improvements in both the macroeconomy and borrowers' characteristics have rendered the identification of the most problematic mortgage pricing determinant difficult, consequently making the targeting of policy interventions problematic. Design/methodology/approach This research sought to resolve this aforementioned difficulty by providing empirical evidence on the relative importance of mortgage pricing determinants. A data set of mortgage rates of selected Ghanaian banking financial institutions from 2003 to 2013 was examined and analysed by applying Fisher's model of interest rates and an ex post analysis of the standard regression coefficients. Findings The risk premium factor emerged as the most important determinant in Ghana compared with the inflation premium and the real risk-free rate, although all are statistically significant and strongly correlated with mortgage rates. Originality/value This study provides an insight on the relative importance of mortgage pricing determinates and subsequent macro-economic guidance to support policy interventions which could reduce mortgage rates/enhance mortgage affordability. The paper specifically aims to engender wider debate and provide guidance to the Ghanaian Government and/or private enterprises that seek to provide affordable mortgages. Further research is proposed which could explore ways of reducing mortgage rates as a means of engendering social equality and adopt innovative international best practice that has already been tried and tested in countries such as South Africa and the USA.